#include <ext/size.h>
#include <Dictionaries/HashedDictionary.h>
#include <Dictionaries/DictionaryBlockInputStream.h>

namespace DB
{

namespace ErrorCodes
{
    extern const int TYPE_MISMATCH;
    extern const int ARGUMENT_OUT_OF_BOUND;
    extern const int BAD_ARGUMENTS;
    extern const int DICTIONARY_IS_EMPTY;
}


HashedDictionary::HashedDictionary(const std::string & name, const DictionaryStructure & dict_struct,
    DictionarySourcePtr source_ptr, const DictionaryLifetime dict_lifetime, bool require_nonempty, BlockPtr saved_block)
    : name{name}, dict_struct(dict_struct), source_ptr{std::move(source_ptr)}, dict_lifetime(dict_lifetime),
        require_nonempty(require_nonempty), saved_block{std::move(saved_block)}
{
    createAttributes();

    try
    {
        loadData();
        calculateBytesAllocated();
    }
    catch (...)
    {
        creation_exception = std::current_exception();
    }

    creation_time = std::chrono::system_clock::now();
}

HashedDictionary::HashedDictionary(const HashedDictionary & other)
    : HashedDictionary{other.name, other.dict_struct, other.source_ptr->clone(), other.dict_lifetime, other.require_nonempty, other.saved_block}
{
}


void HashedDictionary::toParent(const PaddedPODArray<Key> & ids, PaddedPODArray<Key> & out) const
{
    const auto null_value = std::get<UInt64>(hierarchical_attribute->null_values);

    getItemsNumber<UInt64>(*hierarchical_attribute, ids,
        [&] (const size_t row, const UInt64 value) { out[row] = value; },
        [&] (const size_t) { return null_value; });
}


/// Allow to use single value in same way as array.
static inline HashedDictionary::Key getAt(const PaddedPODArray<HashedDictionary::Key> & arr, const size_t idx) { return arr[idx]; }
static inline HashedDictionary::Key getAt(const HashedDictionary::Key & value, const size_t) { return value; }

template <typename ChildType, typename AncestorType>
void HashedDictionary::isInImpl(
    const ChildType & child_ids,
    const AncestorType & ancestor_ids,
    PaddedPODArray<UInt8> & out) const
{
    const auto null_value = std::get<UInt64>(hierarchical_attribute->null_values);
    const auto & attr = *std::get<CollectionPtrType<Key>>(hierarchical_attribute->maps);
    const auto rows = out.size();

    for (const auto row : ext::range(0, rows))
    {
        auto id = getAt(child_ids, row);
        const auto ancestor_id = getAt(ancestor_ids, row);

        while (id != null_value && id != ancestor_id)
        {
            auto it = attr.find(id);
            if (it != std::end(attr))
                id = it->second;
            else
                break;
        }

        out[row] = id != null_value && id == ancestor_id;
    }

    query_count.fetch_add(rows, std::memory_order_relaxed);
}

void HashedDictionary::isInVectorVector(
    const PaddedPODArray<Key> & child_ids,
    const PaddedPODArray<Key> & ancestor_ids,
    PaddedPODArray<UInt8> & out) const
{
    isInImpl(child_ids, ancestor_ids, out);
}

void HashedDictionary::isInVectorConstant(
    const PaddedPODArray<Key> & child_ids,
    const Key ancestor_id,
    PaddedPODArray<UInt8> & out) const
{
    isInImpl(child_ids, ancestor_id, out);
}

void HashedDictionary::isInConstantVector(
    const Key child_id,
    const PaddedPODArray<Key> & ancestor_ids,
    PaddedPODArray<UInt8> & out) const
{
    isInImpl(child_id, ancestor_ids, out);
}


#define DECLARE(TYPE)\
void HashedDictionary::get##TYPE(const std::string & attribute_name, const PaddedPODArray<Key> & ids, ResultArrayType<TYPE> & out) const\
{\
    const auto & attribute = getAttribute(attribute_name);\
    if (!isAttributeTypeConvertibleTo(attribute.type, AttributeUnderlyingType::TYPE))\
        throw Exception{name + ": type mismatch: attribute " + attribute_name + " has type " + toString(attribute.type), ErrorCodes::TYPE_MISMATCH};\
    \
    const auto null_value = std::get<TYPE>(attribute.null_values);\
    \
    getItemsNumber<TYPE>(attribute, ids,\
        [&] (const size_t row, const auto value) { out[row] = value; },\
        [&] (const size_t) { return null_value; });\
}
DECLARE(UInt8)
DECLARE(UInt16)
DECLARE(UInt32)
DECLARE(UInt64)
DECLARE(UInt128)
DECLARE(Int8)
DECLARE(Int16)
DECLARE(Int32)
DECLARE(Int64)
DECLARE(Float32)
DECLARE(Float64)
DECLARE(Decimal32)
DECLARE(Decimal64)
DECLARE(Decimal128)
#undef DECLARE

void HashedDictionary::getString(const std::string & attribute_name, const PaddedPODArray<Key> & ids, ColumnString * out) const
{
    const auto & attribute = getAttribute(attribute_name);
    if (!isAttributeTypeConvertibleTo(attribute.type, AttributeUnderlyingType::String))
        throw Exception{name + ": type mismatch: attribute " + attribute_name + " has type " + toString(attribute.type), ErrorCodes::TYPE_MISMATCH};

    const auto & null_value = StringRef{std::get<String>(attribute.null_values)};

    getItemsImpl<StringRef, StringRef>(attribute, ids,
        [&] (const size_t, const StringRef value) { out->insertData(value.data, value.size); },
        [&] (const size_t) { return null_value; });
}

#define DECLARE(TYPE)\
void HashedDictionary::get##TYPE(\
    const std::string & attribute_name, const PaddedPODArray<Key> & ids, const PaddedPODArray<TYPE> & def,\
    ResultArrayType<TYPE> & out) const\
{\
    const auto & attribute = getAttribute(attribute_name);\
    if (!isAttributeTypeConvertibleTo(attribute.type, AttributeUnderlyingType::TYPE))\
        throw Exception{name + ": type mismatch: attribute " + attribute_name + " has type " + toString(attribute.type), ErrorCodes::TYPE_MISMATCH};\
    \
    getItemsNumber<TYPE>(attribute, ids,\
        [&] (const size_t row, const auto value) { out[row] = value; },\
        [&] (const size_t row) { return def[row]; });\
}
DECLARE(UInt8)
DECLARE(UInt16)
DECLARE(UInt32)
DECLARE(UInt64)
DECLARE(UInt128)
DECLARE(Int8)
DECLARE(Int16)
DECLARE(Int32)
DECLARE(Int64)
DECLARE(Float32)
DECLARE(Float64)
DECLARE(Decimal32)
DECLARE(Decimal64)
DECLARE(Decimal128)
#undef DECLARE

void HashedDictionary::getString(
    const std::string & attribute_name, const PaddedPODArray<Key> & ids, const ColumnString * const def,
    ColumnString * const out) const
{
    const auto & attribute = getAttribute(attribute_name);
    if (!isAttributeTypeConvertibleTo(attribute.type, AttributeUnderlyingType::String))
        throw Exception{name + ": type mismatch: attribute " + attribute_name + " has type " + toString(attribute.type), ErrorCodes::TYPE_MISMATCH};

    getItemsImpl<StringRef, StringRef>(attribute, ids,
        [&] (const size_t, const StringRef value) { out->insertData(value.data, value.size); },
        [&] (const size_t row) { return def->getDataAt(row); });
}

#define DECLARE(TYPE)\
void HashedDictionary::get##TYPE(\
    const std::string & attribute_name, const PaddedPODArray<Key> & ids, const TYPE & def, ResultArrayType<TYPE> & out) const\
{\
    const auto & attribute = getAttribute(attribute_name);\
    if (!isAttributeTypeConvertibleTo(attribute.type, AttributeUnderlyingType::TYPE))\
        throw Exception{name + ": type mismatch: attribute " + attribute_name + " has type " + toString(attribute.type), ErrorCodes::TYPE_MISMATCH};\
    \
    getItemsNumber<TYPE>(attribute, ids,\
        [&] (const size_t row, const auto value) { out[row] = value; },\
        [&] (const size_t) { return def; });\
}
DECLARE(UInt8)
DECLARE(UInt16)
DECLARE(UInt32)
DECLARE(UInt64)
DECLARE(UInt128)
DECLARE(Int8)
DECLARE(Int16)
DECLARE(Int32)
DECLARE(Int64)
DECLARE(Float32)
DECLARE(Float64)
DECLARE(Decimal32)
DECLARE(Decimal64)
DECLARE(Decimal128)
#undef DECLARE

void HashedDictionary::getString(
    const std::string & attribute_name, const PaddedPODArray<Key> & ids, const String & def,
    ColumnString * const out) const
{
    const auto & attribute = getAttribute(attribute_name);
    if (!isAttributeTypeConvertibleTo(attribute.type, AttributeUnderlyingType::String))
        throw Exception{name + ": type mismatch: attribute " + attribute_name + " has type " + toString(attribute.type), ErrorCodes::TYPE_MISMATCH};

    getItemsImpl<StringRef, StringRef>(attribute, ids,
        [&] (const size_t, const StringRef value) { out->insertData(value.data, value.size); },
        [&] (const size_t) { return StringRef{def}; });
}

void HashedDictionary::has(const PaddedPODArray<Key> & ids, PaddedPODArray<UInt8> & out) const
{
    const auto & attribute = attributes.front();

    switch (attribute.type)
    {
        case AttributeUnderlyingType::UInt8: has<UInt8>(attribute, ids, out); break;
        case AttributeUnderlyingType::UInt16: has<UInt16>(attribute, ids, out); break;
        case AttributeUnderlyingType::UInt32: has<UInt32>(attribute, ids, out); break;
        case AttributeUnderlyingType::UInt64: has<UInt64>(attribute, ids, out); break;
        case AttributeUnderlyingType::UInt128: has<UInt128>(attribute, ids, out); break;
        case AttributeUnderlyingType::Int8: has<Int8>(attribute, ids, out); break;
        case AttributeUnderlyingType::Int16: has<Int16>(attribute, ids, out); break;
        case AttributeUnderlyingType::Int32: has<Int32>(attribute, ids, out); break;
        case AttributeUnderlyingType::Int64: has<Int64>(attribute, ids, out); break;
        case AttributeUnderlyingType::Float32: has<Float32>(attribute, ids, out); break;
        case AttributeUnderlyingType::Float64: has<Float64>(attribute, ids, out); break;
        case AttributeUnderlyingType::String: has<StringRef>(attribute, ids, out); break;

        case AttributeUnderlyingType::Decimal32: has<Decimal32>(attribute, ids, out); break;
        case AttributeUnderlyingType::Decimal64: has<Decimal64>(attribute, ids, out); break;
        case AttributeUnderlyingType::Decimal128: has<Decimal128>(attribute, ids, out); break;
    }
}

void HashedDictionary::createAttributes()
{
    const auto size = dict_struct.attributes.size();
    attributes.reserve(size);

    for (const auto & attribute : dict_struct.attributes)
    {
        attribute_index_by_name.emplace(attribute.name, attributes.size());
        attributes.push_back(createAttributeWithType(attribute.underlying_type, attribute.null_value));

        if (attribute.hierarchical)
        {
            hierarchical_attribute = & attributes.back();

            if (hierarchical_attribute->type != AttributeUnderlyingType::UInt64)
                throw Exception{name + ": hierarchical attribute must be UInt64.", ErrorCodes::TYPE_MISMATCH};
        }
    }
}

void HashedDictionary::blockToAttributes(const Block & block)
{
    const auto & id_column = *block.safeGetByPosition(0).column;
    element_count += id_column.size();

    for (const size_t attribute_idx : ext::range(0, attributes.size()))
    {
        const IColumn & attribute_column = *block.safeGetByPosition(attribute_idx + 1).column;
        auto & attribute = attributes[attribute_idx];

        for (const auto row_idx : ext::range(0, id_column.size()))
            setAttributeValue(attribute, id_column[row_idx].get<UInt64>(), attribute_column[row_idx]);
    }
}

void HashedDictionary::updateData()
{
    if (!saved_block || saved_block->rows() == 0)
    {
        auto stream = source_ptr->loadUpdatedAll();
        stream->readPrefix();

        while (const auto block = stream->read())
        {
            /// We are using this to keep saved data if input stream consists of multiple blocks
            if (!saved_block)
                saved_block = std::make_shared<DB::Block>(block.cloneEmpty());
            for (const auto attribute_idx : ext::range(0, attributes.size() + 1))
            {
                const IColumn & update_column = *block.getByPosition(attribute_idx).column.get();
                MutableColumnPtr saved_column = saved_block->getByPosition(attribute_idx).column->assumeMutable();
                saved_column->insertRangeFrom(update_column, 0, update_column.size());
            }
        }
        stream->readSuffix();
    }
    else
    {
        auto stream = source_ptr->loadUpdatedAll();
        stream->readPrefix();

        while (Block block = stream->read())
        {
            const auto &saved_id_column = *saved_block->safeGetByPosition(0).column;
            const auto &update_id_column = *block.safeGetByPosition(0).column;

            std::unordered_map<Key, std::vector<size_t>> update_ids;
            for (size_t row = 0; row < update_id_column.size(); ++row)
            {
                const auto id = update_id_column.get64(row);
                update_ids[id].push_back(row);
            }

            const size_t saved_rows = saved_id_column.size();
            IColumn::Filter filter(saved_rows);
            std::unordered_map<Key, std::vector<size_t>>::iterator it;

            for (size_t row = 0; row < saved_id_column.size(); ++row)
            {
                auto id = saved_id_column.get64(row);
                it = update_ids.find(id);

                if (it != update_ids.end())
                    filter[row] = 0;
                else
                    filter[row] = 1;
            }

            auto block_columns = block.mutateColumns();
            for (const auto attribute_idx : ext::range(0, attributes.size() + 1))
            {
                auto & column = saved_block->safeGetByPosition(attribute_idx).column;
                const auto & filtered_column = column->filter(filter, -1);

                block_columns[attribute_idx]->insertRangeFrom(*filtered_column.get(), 0, filtered_column->size());
            }

            saved_block->setColumns(std::move(block_columns));
        }
        stream->readSuffix();
    }

    if (saved_block)
        blockToAttributes(*saved_block.get());
}

void HashedDictionary::loadData()
{
    if (!source_ptr->hasUpdateField())
    {
        auto stream = source_ptr->loadAll();
        stream->readPrefix();

        while (const auto block = stream->read())
            blockToAttributes(block);

        stream->readSuffix();
    }
    else
        updateData();

    if (require_nonempty && 0 == element_count)
        throw Exception{name + ": dictionary source is empty and 'require_nonempty' property is set.", ErrorCodes::DICTIONARY_IS_EMPTY};
}

template <typename T>
void HashedDictionary::addAttributeSize(const Attribute & attribute)
{
    const auto & map_ref = std::get<CollectionPtrType<T>>(attribute.maps);
    bytes_allocated += sizeof(CollectionType<T>) + map_ref->getBufferSizeInBytes();
    bucket_count = map_ref->getBufferSizeInCells();
}

void HashedDictionary::calculateBytesAllocated()
{
    bytes_allocated += attributes.size() * sizeof(attributes.front());

    for (const auto & attribute : attributes)
    {
        switch (attribute.type)
        {
            case AttributeUnderlyingType::UInt8: addAttributeSize<UInt8>(attribute); break;
            case AttributeUnderlyingType::UInt16: addAttributeSize<UInt16>(attribute); break;
            case AttributeUnderlyingType::UInt32: addAttributeSize<UInt32>(attribute); break;
            case AttributeUnderlyingType::UInt64: addAttributeSize<UInt64>(attribute); break;
            case AttributeUnderlyingType::UInt128: addAttributeSize<UInt128>(attribute); break;
            case AttributeUnderlyingType::Int8: addAttributeSize<Int8>(attribute); break;
            case AttributeUnderlyingType::Int16: addAttributeSize<Int16>(attribute); break;
            case AttributeUnderlyingType::Int32: addAttributeSize<Int32>(attribute); break;
            case AttributeUnderlyingType::Int64: addAttributeSize<Int64>(attribute); break;
            case AttributeUnderlyingType::Float32: addAttributeSize<Float32>(attribute); break;
            case AttributeUnderlyingType::Float64: addAttributeSize<Float64>(attribute); break;

            case AttributeUnderlyingType::Decimal32: addAttributeSize<Decimal32>(attribute); break;
            case AttributeUnderlyingType::Decimal64: addAttributeSize<Decimal64>(attribute); break;
            case AttributeUnderlyingType::Decimal128: addAttributeSize<Decimal128>(attribute); break;

            case AttributeUnderlyingType::String:
            {
                addAttributeSize<StringRef>(attribute);
                bytes_allocated += sizeof(Arena) + attribute.string_arena->size();

                break;
            }
        }
    }
}

template <typename T>
void HashedDictionary::createAttributeImpl(Attribute & attribute, const Field & null_value)
{
    attribute.null_values = T(null_value.get<NearestFieldType<T>>());
    attribute.maps = std::make_unique<CollectionType<T>>();
}

HashedDictionary::Attribute HashedDictionary::createAttributeWithType(const AttributeUnderlyingType type, const Field & null_value)
{
    Attribute attr{type, {}, {}, {}};

    switch (type)
    {
        case AttributeUnderlyingType::UInt8: createAttributeImpl<UInt8>(attr, null_value); break;
        case AttributeUnderlyingType::UInt16: createAttributeImpl<UInt16>(attr, null_value); break;
        case AttributeUnderlyingType::UInt32: createAttributeImpl<UInt32>(attr, null_value); break;
        case AttributeUnderlyingType::UInt64: createAttributeImpl<UInt64>(attr, null_value); break;
        case AttributeUnderlyingType::UInt128: createAttributeImpl<UInt128>(attr, null_value); break;
        case AttributeUnderlyingType::Int8: createAttributeImpl<Int8>(attr, null_value); break;
        case AttributeUnderlyingType::Int16: createAttributeImpl<Int16>(attr, null_value); break;
        case AttributeUnderlyingType::Int32: createAttributeImpl<Int32>(attr, null_value); break;
        case AttributeUnderlyingType::Int64: createAttributeImpl<Int64>(attr, null_value); break;
        case AttributeUnderlyingType::Float32: createAttributeImpl<Float32>(attr, null_value); break;
        case AttributeUnderlyingType::Float64: createAttributeImpl<Float64>(attr, null_value); break;

        case AttributeUnderlyingType::Decimal32: createAttributeImpl<Decimal32>(attr, null_value); break;
        case AttributeUnderlyingType::Decimal64: createAttributeImpl<Decimal64>(attr, null_value); break;
        case AttributeUnderlyingType::Decimal128: createAttributeImpl<Decimal128>(attr, null_value); break;

        case AttributeUnderlyingType::String:
        {
            attr.null_values = null_value.get<String>();
            attr.maps = std::make_unique<CollectionType<StringRef>>();
            attr.string_arena = std::make_unique<Arena>();
            break;
        }
    }

    return attr;
}


template <typename OutputType, typename ValueSetter, typename DefaultGetter>
void HashedDictionary::getItemsNumber(
    const Attribute & attribute,
    const PaddedPODArray<Key> & ids,
    ValueSetter && set_value,
    DefaultGetter && get_default) const
{
    if (false) {}
#define DISPATCH(TYPE) \
    else if (attribute.type == AttributeUnderlyingType::TYPE) \
        getItemsImpl<TYPE, OutputType>(attribute, ids, std::forward<ValueSetter>(set_value), std::forward<DefaultGetter>(get_default));
    DISPATCH(UInt8)
    DISPATCH(UInt16)
    DISPATCH(UInt32)
    DISPATCH(UInt64)
    DISPATCH(UInt128)
    DISPATCH(Int8)
    DISPATCH(Int16)
    DISPATCH(Int32)
    DISPATCH(Int64)
    DISPATCH(Float32)
    DISPATCH(Float64)
    DISPATCH(Decimal32)
    DISPATCH(Decimal64)
    DISPATCH(Decimal128)
#undef DISPATCH
    else
        throw Exception("Unexpected type of attribute: " + toString(attribute.type), ErrorCodes::LOGICAL_ERROR);
}

template <typename AttributeType, typename OutputType, typename ValueSetter, typename DefaultGetter>
void HashedDictionary::getItemsImpl(
    const Attribute & attribute,
    const PaddedPODArray<Key> & ids,
    ValueSetter && set_value,
    DefaultGetter && get_default) const
{
    const auto & attr = *std::get<CollectionPtrType<AttributeType>>(attribute.maps);
    const auto rows = ext::size(ids);

    for (const auto i : ext::range(0, rows))
    {
        const auto it = attr.find(ids[i]);
        set_value(i, it != attr.end() ? static_cast<OutputType>(it->second) : get_default(i));
    }

    query_count.fetch_add(rows, std::memory_order_relaxed);
}


template <typename T>
void HashedDictionary::setAttributeValueImpl(Attribute & attribute, const Key id, const T value)
{
    auto & map = *std::get<CollectionPtrType<T>>(attribute.maps);
    map.insert({ id, value });
}

void HashedDictionary::setAttributeValue(Attribute & attribute, const Key id, const Field & value)
{
    switch (attribute.type)
    {
        case AttributeUnderlyingType::UInt8: setAttributeValueImpl<UInt8>(attribute, id, value.get<UInt64>()); break;
        case AttributeUnderlyingType::UInt16: setAttributeValueImpl<UInt16>(attribute, id, value.get<UInt64>()); break;
        case AttributeUnderlyingType::UInt32: setAttributeValueImpl<UInt32>(attribute, id, value.get<UInt64>()); break;
        case AttributeUnderlyingType::UInt64: setAttributeValueImpl<UInt64>(attribute, id, value.get<UInt64>()); break;
        case AttributeUnderlyingType::UInt128: setAttributeValueImpl<UInt128>(attribute, id, value.get<UInt128>()); break;
        case AttributeUnderlyingType::Int8: setAttributeValueImpl<Int8>(attribute, id, value.get<Int64>()); break;
        case AttributeUnderlyingType::Int16: setAttributeValueImpl<Int16>(attribute, id, value.get<Int64>()); break;
        case AttributeUnderlyingType::Int32: setAttributeValueImpl<Int32>(attribute, id, value.get<Int64>()); break;
        case AttributeUnderlyingType::Int64: setAttributeValueImpl<Int64>(attribute, id, value.get<Int64>()); break;
        case AttributeUnderlyingType::Float32: setAttributeValueImpl<Float32>(attribute, id, value.get<Float64>()); break;
        case AttributeUnderlyingType::Float64: setAttributeValueImpl<Float64>(attribute, id, value.get<Float64>()); break;

        case AttributeUnderlyingType::Decimal32: setAttributeValueImpl<Decimal32>(attribute, id, value.get<Decimal32>()); break;
        case AttributeUnderlyingType::Decimal64: setAttributeValueImpl<Decimal64>(attribute, id, value.get<Decimal64>()); break;
        case AttributeUnderlyingType::Decimal128: setAttributeValueImpl<Decimal128>(attribute, id, value.get<Decimal128>()); break;

        case AttributeUnderlyingType::String:
        {
            auto & map = *std::get<CollectionPtrType<StringRef>>(attribute.maps);
            const auto & string = value.get<String>();
            const auto string_in_arena = attribute.string_arena->insert(string.data(), string.size());
            map.insert({ id, StringRef{string_in_arena, string.size()} });
            break;
        }
    }
}

const HashedDictionary::Attribute & HashedDictionary::getAttribute(const std::string & attribute_name) const
{
    const auto it = attribute_index_by_name.find(attribute_name);
    if (it == std::end(attribute_index_by_name))
        throw Exception{name + ": no such attribute '" + attribute_name + "'", ErrorCodes::BAD_ARGUMENTS};

    return attributes[it->second];
}

template <typename T>
void HashedDictionary::has(const Attribute & attribute, const PaddedPODArray<Key> & ids, PaddedPODArray<UInt8> & out) const
{
    const auto & attr = *std::get<CollectionPtrType<T>>(attribute.maps);
    const auto rows = ext::size(ids);

    for (const auto i : ext::range(0, rows))
        out[i] = attr.find(ids[i]) != std::end(attr);

    query_count.fetch_add(rows, std::memory_order_relaxed);
}

template <typename T>
PaddedPODArray<HashedDictionary::Key> HashedDictionary::getIds(const Attribute & attribute) const
{
    const HashMap<UInt64, T> & attr = *std::get<CollectionPtrType<T>>(attribute.maps);

    PaddedPODArray<Key> ids;
    ids.reserve(attr.size());
    for (const auto & value : attr)
        ids.push_back(value.first);

    return ids;
}

PaddedPODArray<HashedDictionary::Key> HashedDictionary::getIds() const
{
    const auto & attribute = attributes.front();

    switch (attribute.type)
    {
        case AttributeUnderlyingType::UInt8: return getIds<UInt8>(attribute);
        case AttributeUnderlyingType::UInt16: return getIds<UInt16>(attribute);
        case AttributeUnderlyingType::UInt32: return getIds<UInt32>(attribute);
        case AttributeUnderlyingType::UInt64: return getIds<UInt64>(attribute);
        case AttributeUnderlyingType::UInt128: return getIds<UInt128>(attribute);
        case AttributeUnderlyingType::Int8: return getIds<Int8>(attribute);
        case AttributeUnderlyingType::Int16: return getIds<Int16>(attribute);
        case AttributeUnderlyingType::Int32: return getIds<Int32>(attribute);
        case AttributeUnderlyingType::Int64: return getIds<Int64>(attribute);
        case AttributeUnderlyingType::Float32: return getIds<Float32>(attribute);
        case AttributeUnderlyingType::Float64: return getIds<Float64>(attribute);
        case AttributeUnderlyingType::String: return getIds<StringRef>(attribute);

        case AttributeUnderlyingType::Decimal32: return getIds<Decimal32>(attribute);
        case AttributeUnderlyingType::Decimal64: return getIds<Decimal64>(attribute);
        case AttributeUnderlyingType::Decimal128: return getIds<Decimal128>(attribute);
    }
    return PaddedPODArray<Key>();
}

BlockInputStreamPtr HashedDictionary::getBlockInputStream(const Names & column_names, size_t max_block_size) const
{
    using BlockInputStreamType = DictionaryBlockInputStream<HashedDictionary, Key>;
    return std::make_shared<BlockInputStreamType>(shared_from_this(), max_block_size, getIds(), column_names);
}

}
